Jacob, Jeffrey T.

OBJECT Nonpowder guns, defined as spring- or gas-powered BB or pellet guns, can be dangerous weapons that are often marketed to children. In recent decades, advances in compressed-gas technology have led to a significant increase in the power and muzzle velocity of these weapons. The risk of intracranial injury in children due to nonpowder weapons is poorly documented. METHODS A retrospective review was conducted at 3 institutions studying children 16 years or younger who had intracranial injuries secondary to nonpowder guns. RESULTS The authors reviewed 14 cases of intracranial injury in children from 3 institutions. Eleven (79%) of the 14 children were injured by BB guns, while 3 (21%) were injured by pellet guns. In 10 (71%) children, the injury was accidental. There was 1 recognized assault, but there were no suicide attempts; in the remaining 3 patients, the intention was indeterminate. There were no mortalities among the patients in this series. Ten (71%) of the children required operative intervention, and 6 (43%) were left with permanent neurological injuries, including epilepsy, cognitive deficits, hydrocephalus, diplopia, visual field cut, and blindness. CONCLUSIONS Nonpowder guns are weapons with the ability to penetrate a child’s skull and brain. Awareness should be raised among parents, children, and policy makers as to the risk posed by these weapons.

ObjectiveTo characterize the evolving management of vestibular schwannoma (VS) in the United States.Study DesignRetrospective analysis of the Surveillance, Epidemiology, and End Results (SEER) database.SettingSEER database.Subjects and MethodsAll patients with a diagnosis of VS were analyzed. Data were described and compared using trend analyses and univariate and multivariable logistic regression.ResultsA total of 8330 patients (average age 54.7 years, 51.9% female) were analyzed. The mean incidence was approximately 1.1 per 100,000 per year and did not vary significantly across time; however, from 2004 to 2011, there was a statistically significant decrease in tumor size category at time of diagnosis (P <. 01). Overall, 3982 patients (48%) received primary microsurgery, 1978 (24%) radiation therapy alone, and 2370 (29%) observation. Within the microsurgical cohort, 732 (18%) underwent subtotal resection, and of those, 98 (13.4%) received postoperative radiation therapy. Multivariable regression revealed that surgical treatment was more common in younger patients and larger tumor size categories (P <. 05). Management trend analysis revealed that microsurgery was used less frequently over time (P <. 0001), observation was used more frequently (P <. 0001), and the pattern of radiation therapy remained unchanged. Linear regression was used to create an equation that was applied to predict future management practices. These data predict that by 2026, half of all cases of VS will be managed initially with observation.ConclusionWhile the incidence of VS has remained steady, tumor size at time of diagnosis has decreased over time. Within the United States there has been a clear, recent evolution in management toward observation.

This report reviews a series of 3 patients who developed superficial siderosis following posterior fossa operations in which dural closure was incomplete. In all 3 patients, revision surgery and complete duraplasty was performed to halt the progression of superficial siderosis. Following surgery, 2 patients experienced resolution of their CSF xanthochromia while 1 patient had reduced CSF xanthochromia. In this paper the authors also review the etiology, pathophysiology, diagnosis, and treatment of this condition. The authors suggest that posterior fossa dural patency and pseudomeningocele are risk factors for the latent development of superficial siderosis and recommend that revision duraplasty be performed in patients with posterior fossa pseudomeningoceles and superficial siderosis to prevent progression of the disease.

Study Design Retrospective case series. Objective To determine the effect of obesity on the resource utilization and cost in 3270 consecutive patients undergoing elective noninstrumented decompressive surgeries for degenerative spine disease at Mayo Clinic Rochester between 2005 and 2012. Methods Groups were assessed for baseline differences (age, gender, and American Society of Anesthesiologists [ASA] classification, procedure type, and number of operative levels). Outcome variables included the transfusion requirements during surgery, the total anesthesia and surgical times, intensive care unit (ICU) admissions, standardized costs, as well as the ICU and hospital length of stay (LOS). Regression analysis was used to evaluate for strength of association between obesity and outcome variables. Results Baseline differences between the groups (nonobese: n = 1,853; obese: n = 1,417) were found with respect to age, ASA class, gender, procedure type, and number of operative levels. After correcting for differences, we found significant associations between obesity and surgical ( p < 0.0001) and anesthesia times ( p < 0.0001) and hospital LOS ( p < 0.0001). Additionally, ICU admission rates ( p = 0.02) and requirement for postoperative ventilation ( p = 0.048) were significantly higher in obese patients. Finally, mean difference in total cost ($1,632, p < 0.0001) was significantly higher for the obese cohort. Conclusion Obesity is associated with increased resource utilization and cost in patients undergoing a noninstrumented decompressive surgery for degenerative spine disease.

Object The goals of this retrospective cohort study were as follows: 1) to describe the long-term prevalence and timing of hearing deterioration following low-dose (12- to 13-Gy marginal dose) stereotactic radiosurgery (SRS) for vestibular schwannoma (VS); and 2) to identify clinical variables associated with long-term preservation of useful hearing following treatment. Methods Patients with serviceable hearing who underwent SRS for VS between 1997 and 2002 were studied. Data including radiosurgery treatment plans, tumor characteristics, pre- and posttreatment pure tone average, speech discrimination scores, and American Academy of Otolaryngology–Head and Neck Surgery hearing class were collected. Time to nonserviceable hearing was estimated using the Kaplan-Meier method. Univariate and multivariate associations with time to nonserviceable hearing were evaluated using Cox proportional hazards regression models. Results Forty-four patients met the study criteria and were included. The median duration of audiometric follow-up was 9.3 years. Thirty-six patients developed nonserviceable hearing at a mean of 4.2 years following SRS. The Kaplan-Meier estimated rates of serviceable hearing at 1, 3, 5, 7, and 10 years following SRS were 80%, 55%, 48%, 38%, and 23%, respectively. Multivariate analysis revealed that pretreatment ipsilateral pure tone average (p < 0.001) and tumor size (p = 0.009) were statistically significantly associated with time to nonserviceable hearing. Conclusions Durable hearing preservation a decade after low-dose SRS for VS occurs in less than one-fourth of patients. Variables including preoperative hearing capacity and tumor size may be used to predict hearing outcomes following treatment. These findings may assist in pretreatment risk disclosure. Furthermore, these data demonstrate the importance of long-term follow-up when reporting audiometric outcomes following SRS for VS.

Object The authors reviewed outcomes after stereotactic radiosurgery for patients with acromegaly and analyzed factors associated with biochemical remission. Methods Retrospective analysis was performed for 46 consecutive cases of growth hormone (GH)–producing pituitary adenomas treated by radiosurgery between 1991 and 2004. Biochemical remission was defined as a fasting GH less than 2 ng/ml and a normal age- and sex-adjusted insulin-like growth factor–I (IGF-I) level while patients were not receiving any pituitary suppressive medications. The median follow up after radiosurgery was 63 months (range 22–168 months). Twenty-three patients (50%) had biochemical remission documented at a median of 36 months (range 6–63 months) after one radiosurgical procedure. The actuarial rates of biochemical remission at 2 and 5 years after radiosurgery were 11 and 60%, respectively. Multivariate analysis showed that IGF-I levels less than 2.25 times the upper limit of normal (hazard ratio [HR] 2.9, 95% confidence interval [CI] 1.2–6.9, p = 0.02) and the absence of pituitary suppressive medications at the time of radiosurgery (HR 4.2, 95% CI 1.4–13.2, p = 0.01) correlated with biochemical remission. The incidence of new anterior pituitary deficits was 10% at 2 years and 33% at 5 years. Conclusions Discontinuation of pituitary suppressive medications at least 1 month before radiosurgery significantly improved endocrine outcomes for patients with acromegaly. Patients with GH–producing pituitary adenomas should not undergo further radiation therapy or surgery for at least 5 years after radiosurgery because GH and IGF-I levels continue to normalize over that interval.

Object The purpose of this study was to examine the prevalence of intracranial cavernous malformations (CMs) in a large series of predominantly Caucasian patients with spinal cord CMs. The authors also studied the natural history of spinal CMs in patients who were treated nonoperatively. Methods The medical records of 67 consecutive patients (32 female and 35 male patients) in whom a spinal CM was diagnosed between 1994 and 2002 were reviewed. The patients’ mean age at presentation was 50 years (range 13–82 years). Twenty-five patients underwent resection of the lesion. Forty-two patients in whom the spinal CM was diagnosed using magnetic resonance (MR) imaging were followed expectantly. Thirty-three (49%) of 67 patients underwent both spinal and intracranial MR imaging. All available imaging studies were reviewed to determine the coexistence of an intracranial CM. Fourteen (42%) of the 33 patients with spinal CMs who underwent intracranial MR imaging harbored at least one cerebral CM in addition to the spinal lesion. Six (43%) of these 14 patients did not have a known family history of CM. Data obtained during the long-term follow-up period (mean 9.7 years, total of 319 patient-years) were available for 33 of the 42 patients with a spinal CM who did not undergo surgery. Five symptomatic lesional hemorrhages (neurological events), four of which were documented on neuroimaging studies, occurred during the follow-up period, for an overall event rate of 1.6% per patient per year. No patient experienced clinically significant neurological deficits due to recurrent hemorrhage. Conclusions As many as 40% of patients with a spinal CM may harbor a similar intracranial lesion, and approximately 40% of patients with coexisting spinal and intracranial CMs may have the nonfamilial (sporadic) form of the disease. Patients with symptomatic spinal CMs who are treated nonoperatively may have a small risk of clinically significant recurrent hemorrhage. The findings will aid in evaluation of surveillance images and in counseling of patients with spinal CMs, irrespective of family history.